CO2 reduction options in cement industry: The Novi Popovac case

The cement industry contributes about 5% to global anthropogenic CO2 emissions, and is thus an important sector in CO2-emission mitigation strategies. Carbon dioxide is emitted from the calcination process of limestone, from combustion of fuels in the kiln, and from the coal combustion during power generation. Strategies to reduce these CO2 emissions include energy efficiency improvement, new processes, shift to low carbon fuels or waste fuels in cement production, increased use of additives in cement production, alternative cements, and CO2 removal from flue gases in clinker kilns. Increased use of fly ash as an additive to cement and concrete has a number of advantages, the primary being reduction of costs of fly ash disposal, resource conservation, and cost reduction of the product. Since the production of cement requires a large amount of energy (about 2.9-3.2 GJt-1), the substitution of cement by fly ash saves not only energy but also reduces the associated greenhouse gas emissions. The paper evaluates the reduction of CO2 emissions that can be achieved by these mitigation strategies, as well as by partial substitution of cement by fly ash. The latter is important because the quality of the produced concrete depends on the physical-chemical properties of the fly ash and thus partial substitution as well as the type of fly ash (e.g., the content of CaO) has an effect not only on energy consumption and emissions, but also on the produced concrete quality.

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Thermoactivated Recycled Cement

10.5772/intechopen.98488 ◽

2021 ◽

Author(s):

José Alexandre Bogas ◽

Ana Carriço ◽

Sofia Real

Keyword(s):

Ordinary Portland Cement ◽

Ghg Emissions ◽

Resource Depletion ◽

Cement Industry ◽

Future Perspective ◽

Low Carbon ◽

Cement Production ◽

Waste Concrete ◽

Cement Based Materials ◽

Main Production

The cement industry is currently faced by the great challenge of reducing its vast carbon footprint, due to being the second highest industrial greenhouse gases (GHG) emitter. This value is expected to further increase, since cement production is foreseen to rise by about 20% until 2050. Therefore, more eco-efficient alternatives to ordinary Portland cement have been developed towards a sustainable concrete industry. This chapter presents some of the latest advances in low-carbon thermoactivated recycled cements (RC) obtained from old waste concrete, leading to a significant reduction of the GHG emissions, while also encouraging the valorization reuse of waste materials and the reduction of natural resource depletion. The manufacture and general performance of RC, including the main production issues, rehydration behavior and phase and microstructure development, as well as its incorporation in cement-based materials are discussed. Some of the most recent research, main challenges and future perspective of RC are addressed.

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Provincial-Level CO2 Emissions Intensity Inequality in China: Regional Source and Explanatory Factors of Interregional and Intraregional Inequalities

Sustainability ◽

10.3390/su12062529 ◽

2020 ◽

Vol 12 (6) ◽

pp. 2529

Author(s):

Wanbei Jiang ◽

Weidong Liu

Keyword(s):

Energy Efficiency ◽

Co2 Emissions ◽

Mitigation Strategies ◽

Central China ◽

Western China ◽

Theil Index ◽

Chinese Government ◽

Emission Mitigation ◽

Provincial Level ◽

Emissions Intensity

As the largest emitter in the world, China has pledged to reduce CO2 emissions intensity (CO2 emissions per unit of output) by 60–65% between 2005 and 2030. CO2 emissions intensity inequality analysis in China can provide a scientific basis for the Chinese government to formulate reasonable regional carbon emission abatement strategies, so as to realize the goal above. This paper adopted the Theil index to study the provincial-level CO2 emissions intensity inequality in China during 2005–2015. The regional decomposition was firstly conducted and then the factors of interregional and intraregional inequalities were explored. The results show: (i) a clear increase in provincial CO2 emissions intensity inequality in China has happened; (ii) this inequality and its increase were both mainly explained by the intraregional component; and (iii) the energy efficiency was the most important and positive contributor in the interregional, Eastern, Central, and Western China inequalities. Energy efficiency was also the key factor that caused the growth in interregional and Western China inequalities. However, most of the Eastern and Central China inequality increments over the whole period were respectively driven by the expanding carbonization gap and the changing GDP share, instead of the trajectory of energy efficiency. According to the results, regional emission mitigation strategies were proposed.

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The Study of the Properties of Concrete Containing Waste Powder as a Fine Aggregate

Proccedings of 10th International Conference "Environmental Engineering" ◽

10.3846/enviro.2017.016 ◽

2017 ◽

Cited By ~ 1

Author(s):

Magdalena Dobiszewska ◽

Krzysztof Wrzecion

Keyword(s):

Asphalt Mixture ◽

Cement Industry ◽

Partial Substitution ◽

Partial Replacement ◽

Economic Losses ◽

Fine Aggregate ◽

Natural Sand ◽

Cement Production ◽

Freeze Resistance ◽

Concrete Production

Concrete production consumes much energy and large amounts of natural resources. It causes environmental, energy and economic losses. Cement industry contributes to production for about 7% of all CO2 generated in the world. Every ton of cement production releases nearly one ton of CO2 to atmosphere. Thus the concrete and cement industry changes the environment appearance and affects it to a great extent. On the other hand, there is an increase in demand and decrease in natural sources of concrete constituents, like sand. The use of rock dust as the replacement for natural sand will solve the problem of dust disposal. The present study shows the results of the research concerning the modi-fication of concrete with waste dust. It is the waste from the preparation of aggregate used in asphalt mixture production. Concrete modification consists in that the powder waste is added to concrete as partial replacement of fine aggregate. Previous studies have shown that analysed waste has a beneficial effect on compressive strength, flexural strength as well as freeze resistance. The use of mineral powder as the partial substitution of fine aggregate allows for the effective management of industrial waste and improves some properties of concrete.

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Research Progress on Low-Carbon Technologies and Assessment Methods in Cement Industry

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1035.933 ◽

2021 ◽

Vol 1035 ◽

pp. 933-943

Author(s):

Hai Tao Zhao ◽

Yu Liu ◽

Xiao Qing Li ◽

Li Wei Hao

Keyword(s):

Ghg Emissions ◽

Assessment Methods ◽

Cement Industry ◽

Research Progress ◽

Main Trend ◽

Low Carbon ◽

Cement Production ◽

Technology And Assessment ◽

Manufacturing Technologies ◽

Low Carbon Technologies

As one of the pillar industries for social development and economic construction, cement manufacture is energy and carbon-intensive, whose greenhouse gas (GHG) emissions account for more than 6% of total global man-made GHG emission annually. With the growing attention on the problem of global warming, researching and promoting low-carbon manufacturing technologies to reduce GHG emissions have become the main trend in the development of cement industry under the new era. This article sorted out the low-carbon technologies for cement production reported in recent years, introduced the mainstream methods of GHG accounting and assessment such as life cycle assessment (LCA) and carbon footprint analysis (CFA), meanwhile reviewed the articles in the field of low-carbon technology and assessment methods in cement production, moreover, discussed the merits and demerits of various assessment methods and applicable fields, in order to provide suggestions and supports for low-carbon transformation of cement industry.

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INVESTIGATION ON ALKALI ACTIVATED FLY ASH BASED GEOPOLYMER CONCRETE

10.37516/global.j.civ.eng.2019.0077 ◽

2019 ◽

pp. 12-15 ◽

Cited By ~ 1

Author(s):

S. L. Hake ◽

S. A. Urphate ◽

P. R. Awasarmal ◽

R. M. Damgir

Keyword(s):

Fly Ash ◽

Variable Parameter ◽

Rest Period ◽

Cement Industry ◽

Curing Temperature ◽

Geopolymer Concrete ◽

Curing Time ◽

Greenhouse Gasses ◽

Temperature Optimization ◽

Ash Disposal

Cement industry plays major role for emission of greenhouse gasses. So, there is need for manufacturing of environmental friendly concrete. Geopolymer concrete helps in reduce global warming as well as fly ash disposal problem. This paper presents study the effect of types of curing, temperature, curing time and rest period. These parameters were studies like one variable parameter and other three are fixed parameter. One by one these parameter were finalize. The types of curing analyze with temperature optimization, rest period and curing time of geopolymer concrete. The type of curing like oven, accelerated, membrane, steam, wet and natural sun light (room temperature). The temperature differs like 600C, 900C, 1200C and 1500C. Once the temperature for type of curing is lock then proceed to curing time i.e. 6, 12, 18 and 24 hours. At the end temperature, type of curing and curing time finalize then optimize the rest period or testing age of concrete. The rest period differ like 1, 3, 7, 14, 21, 28, 56 days. In this study these variable are to be analyze with the help of compressive strength of geopolymer concrete.

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Recent Progress in Green Cement Technology Utilizing Low-Carbon Emission Fuels and Raw Materials: A Review

Sustainability ◽

10.3390/su11020537 ◽

2019 ◽

Vol 11 (2) ◽

pp. 537 ◽

Cited By ~ 33

Author(s):

Ali Naqi ◽

Jeong Jang

Keyword(s):

Carbon Dioxide ◽

Carbon Dioxide Emissions ◽

Alternative Fuels ◽

Raw Materials ◽

Low Cost ◽

Cement Industry ◽

Industrial Wastes ◽

Low Carbon ◽

Cement Production ◽

Cement Manufacturing

The cement industry is facing numerous challenges in the 21st century due to depleting natural fuel resources, shortage of raw materials, exponentially increasing cement demand and climate linked environmental concerns. Every tonne of ordinary Portland cement (OPC) produced releases an equivalent amount of carbon dioxide to the atmosphere. In this regard, cement manufactured from locally available minerals and industrial wastes that can be blended with OPC as substitute, or full replacement with novel clinkers to reduce the energy requirements is strongly desirable. Reduction in energy consumption and carbon emissions during cement manufacturing can be achieved by introducing alternative cements. The potential of alternative cements as a replacement of conventional OPC can only be fully realized through detailed investigation of binder properties with modern technologies. Seven prominent alternative cement types are considered in this study and their current position compared to OPC has been discussed. The study provides a comprehensive analysis of options for future cements, and an up-to-date summary of the different alternative fuels and binders that can be used in cement production to mitigate carbon dioxide emissions. In addition, the practicalities and benefits of producing the low-cost materials to meet the increasing cement demand are discussed.

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Global CO<sub>2</sub> uptake of cement in 1930–2019

10.5194/essd-2020-275 ◽

2020 ◽

Author(s):

Rui Guo ◽

Jiaoyue Wang ◽

Longfei Bing ◽

Dan Tong ◽

Philippe Ciais ◽

...

Keyword(s):

Calcium Content ◽

Cement Industry ◽

Cement Kiln ◽

Low Carbon ◽

Uptake Capacity ◽

Cement Production ◽

Dominant Position ◽

High Calcium ◽

Estimation System ◽

Kiln Dust

Abstract. Because of the alkaline nature and high calcium content of cements in general, they serve as a CO2 absorbing agent through carbonation processes, resembling silicate weathering in nature. This carbon uptake capacity of cements could abate some of the CO2 emitted during their production. Given the scale of cement production worldwide (4.10 Gt in 2019), a life-cycle assessment is necessary in determining the actual net carbon impacts of this industry. We adopted a comprehensive analytical model to estimate the amount of CO2 that had been absorbed from 1930 to 2019 in four types of cement materials including concrete, mortar, construction waste and cement kiln dust (CKD). Besides, the process CO2 emission during the same period based on the same datasets was also estimated. The results show that 21.12 Gt CO2 (18.12–24.54 Gt CO2, 95 % CI) had been absorbed in the cements produced from 1930 to 2019, with the 2019 annual figure mounting up to 0.90 Gt CO2 yr−1 (0.76–1.07 Gt CO2, 95 % CI). The cumulative uptake is equivalent to approx. 52 % of the process emission, based on our estimation. In particular, China's dominant position in cement production/consumption in recent decades also gives rise to its uptake being the greatest with a cumulative sink of 6.21 Gt CO2 (4.59–8.32 Gt CO2, 95 % CI) since 1930. Among the four types of cement materials, mortar is estimated to be the greatest contributor (approx. 58 %) to the total uptake. Potentially, our cement emission and uptake estimation system can be updated annually and modified when necessary for future low-carbon transitions in the cement industry. All the data described in this study, including the Monte Carlo uncertainty analysis results, are accessible at https://doi.org/10.5281/zenodo.4064803.

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Mechanical Properties and Microstructure of Low Carbon Binders Manufactured from Calcined Canal Sediments and Ground Granulated Blast Furnace Slag (GGBS)

Sustainability ◽

10.3390/su13169057 ◽

2021 ◽

Vol 13 (16) ◽

pp. 9057

Author(s):

Rachid Hadj Sadok ◽

Walid Maherzi ◽

Mahfoud Benzerzour ◽

Richard Lord ◽

Keith Torrance ◽

...

Keyword(s):

Compressive Strength ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Linear Increase ◽

High Reactivity ◽

Cement Industry ◽

Partial Substitution ◽

Low Carbon ◽

Gas Emissions ◽

Pozzolanic Material

This research study evaluated the effects of adding Scottish canal sediment after calcination at 750 °C in combination with GGBS on hydration, strength and microstructural properties in ternary cement mixtures in order to reduce their carbon footprint (CO2) and cost. A series of physico-chemical, hydration heat, mechanic performance, mercury porosity and microstructure tests or observations was performed in order to evaluate the fresh and hardened properties. The physical and chemical characterisation of the calcined sediments revealed good pozzolanic properties that could be valorised as a potential co-product in the cement industry. The results obtained for mortars with various percentages of calcined sediment confirmed that this represents a previously unrecognised potential source of high reactivity pozzolanic materials. The evolution of the compressive strength for the different types of mortars based on the partial substitution of cement by slag and calcined sediments showed a linear increase in compressive strength for 90 days. The best compressive strengths and porosity were observed in mortars composed of 50% cement, 40% slag and 10% calcined sediment (CSS10%) after 90 days. In conclusion, the addition of calcined canal sediments as an artificial pozzolanic material could improve strength and save significant amounts of energy or greenhouse gas emissions, while potentially contributing to Scotland’s ambitious 2045 net zero target and reducing greenhouse gas emissions by 2050 in the UK and Europe.

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Assessing, Understanding and Unlocking Supplementary Cementitious Materials

RILEM Technical Letters ◽

10.21809/rilemtechlett.2016.12 ◽

2016 ◽

Vol 1 ◽

pp. 50 ◽

Cited By ~ 57

Author(s):

Ruben Snellings

Keyword(s):

Co2 Emissions ◽

Cementitious Materials ◽

Cement Industry ◽

Supplementary Cementitious Materials ◽

Partial Replacement ◽

New Materials ◽

Cement Production ◽

Blended Cements ◽

International Commitments ◽

Roll Out

The partial replacement of Portland clinker by supplementary cementitious materials (SCM) is one of the most popular and effective measures to reduce both costs and CO2 emissions related to cement production. An estimated 800 Mt/y of blast furnace slags, fly ashes and other materials are currently being used as SCM, but still the cement industry accounts for 5-8% of global CO2 emissions. If no further actions are taken, by the year 2050 this share might even rise beyond 25%. There is thus a clear challenge as to how emissions will be kept at bay and sustainability targets set by international commitments and policy documents will be met.Part of the solution will be a further roll-out of blended cements in which SCMs constitute the main part of the binder to which activators such as Portland cement are added. Since supply concerns are being raised for conventional high-quality SCMs it is clear that new materials and beneficiation technologies will need to step in to achieve further progress. This paper presents opportunities and challenges for new SCMs and demonstrates how advances towards more powerful and reliable characterisation techniques help to better understand and exploit SCM reactivity.

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Decomposition Analysis in Electricity Sector Output from Carbon Emissions in China

Sustainability ◽

10.3390/su10093251 ◽

2018 ◽

Vol 10 (9) ◽

pp. 3251 ◽

Cited By ~ 2

Author(s):

Xue-Ting Jiang ◽

Min Su ◽

Rongrong Li

Keyword(s):

Carbon Dioxide ◽

Co2 Emissions ◽

Carbon Emissions ◽

Carbon Dioxide Emissions ◽

Carbon Emission ◽

Decomposition Analysis ◽

Mitigation Strategies ◽

Electricity Sector ◽

Emission Mitigation ◽

Electric Sector

Carbon emissions from China’s electricity sector account for about one-seventh of the global carbon dioxide emissions, or half of China’s carbon dioxide emissions. A better understanding of the relationship between CO2 emissions and electric output would help develop and adjust carbon emission mitigation strategies for China’s electricity sector. Thus, we applied the electricity elasticity of carbon emissions to a decoupling index that we combined with advanced multilevel Logarithmic Mean Divisia Index tools in order to test the carbon emission response to the electric output and the main drivers. Then, we proposed a comparative decoupling stability analysis method. The results show that the electric output effect played the most significant role in increasing CO2 emissions from China’s electric sector. Also, “relative decoupling” was the main state during the study period (1991–2012). Moreover, the electricity elasticity of CO2 emissions had a better performance regarding stability in the analysis of China’s electricity output.

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